When is the "Electrical Baseline" established in a PSG recording?

The "Electrical Baseline" in a polysomnography (PSG) recording is established when power to the PSG system is turned on. This process involves calibrating the equipment to set a reference point for the electrical activity that will be recorded during the sleep study. The baseline is crucial because it allows the technologist to identify and assess various physiological signals, such as brain waves, muscle activity, and heart rhythms, in relation to this initial reference.

Establishing the baseline at power-on ensures that any variations in the recorded signals can be accurately interpreted as the patient moves through different sleep stages or experiences wakefulness. Properly setting the baseline is essential for the overall quality and reliability of the PSG data collected during the evaluation of sleep patterns and disorders.